UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (date of earliest event reported): October 27, 2014

CARRIZO OIL & GAS, INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (713) 328-1000

Not applicable

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Purchase Agreement

On October 27, 2014, Carrizo Oil & Gas, Inc. (the “Company”) and its wholly owned subsidiaries Bandelier Pipeline Holding, LLC, Carrizo (Eagle Ford) LLC, Carrizo (Marcellus) LLC, Carrizo (Marcellus) WV LLC, Carrizo (Niobrara) LLC, Carrizo (Utica) LLC, Carrizo Marcellus Holding Inc., CLLR, Inc., Hondo Pipeline, Inc. and Mescalero Pipeline, LLC (collectively, the “Subsidiary Guarantors”) entered into a Purchase Agreement (the “Purchase Agreement”) with Wells Fargo Securities, LLC, RBC Capital Markets, LLC and Citigroup Global Markets Inc. as representatives of a group of initial purchasers (collectively, the “Initial Purchasers”), pursuant to which the Company agreed to sell $300 million aggregate principal amount of the Company’s 7.50% Senior Notes due 2020 (the “Senior Notes”). The Senior Notes were offered and sold in a transaction exempt from the registration requirements under the Securities Act of 1933, as amended (the “Securities Act”). The Senior Notes were resold to qualified institutional buyers in reliance on Rule 144A under the Securities Act and to non-U.S. persons in reliance on Regulation S. The offering closed on October 30, 2014.

The Purchase Agreement contains customary representations and warranties of the parties and indemnification and contribution provisions under which the Company and the Subsidiary Guarantors, on one hand, and the Initial Purchasers, on the other, have agreed to indemnify each other against certain liabilities, including liabilities under the Securities Act.

The Company intends to use the net proceeds from the offering to fund the acquisition of additional leasehold and producing interests in the Eagle Ford Shale from Eagle Ford Minerals, LLC (the “Eagle Ford Shale Transaction”) for a purchase price of $243.0 million, net of working capital adjustments ($93.0 million of which was paid at the closing of such transaction, and which was funded from borrowings under the revolving credit facility that will be repaid with net proceeds from this offering), repay amounts outstanding under our revolving credit facility and for general corporate purposes. The remaining $150.0 million will be paid on a deferred basis no later than February 16, 2015 with borrowings under the existing revolving credit facility. Until net proceeds are used to pay the deferred portion of the Eagle Ford Shale Transaction purchase price, net proceeds will be used to repay amounts outstanding under the revolving credit facility.

The foregoing description of the Purchase Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the agreement, which is attached as Exhibit 1.1 to this Current Report and incorporated by reference herein.

Registration Rights Agreement

In connection with the issuance and sale of the Senior Notes, on October 30, 2014, the Company and the Subsidiary Guarantors entered into a Registration Rights Agreement (the “Registration Rights Agreement”) with Wells Fargo Securities, LLC, RBC Capital Markets, LLC and Citigroup Global Markets Inc. as representatives of the Initial Purchasers. Under the Registration Rights Agreement, the Company and the Subsidiary Guarantors agreed to use their commercially reasonable best efforts to file with the United States Securities and Exchange Commission and cause to become effective a registration statement relating to an offer to issue

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new notes having terms substantially identical to the Senior Notes in exchange for outstanding Senior Notes. In certain circumstances, the Company and the Subsidiary Guarantors may be required to use commercially reasonable efforts to file a shelf registration statement to cover resales of the Senior Notes. The Company may be required to pay additional interest to holders of the Senior Notes under certain circumstances in connection with its obligations under the Registration Rights Agreement.

The foregoing description of the Registration Rights Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the agreement, which is attached as Exhibit 10.1 to this Current Report and incorporated by reference herein.

The information provided under Item 2.03 of this Current Report is incorporated into this Item 1.01 by reference.

Item 2.03 Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.

Supplemental Indenture, Indenture and Senior Notes

The Senior Notes described under Item 1.01 of this Current Report were issued pursuant to the indenture dated as of May 28, 2008, among the Company, certain of its subsidiaries named therein and the Trustee (the “Base Indenture”), as supplemented by the fifteenth supplemental indenture thereto dated as of October 30, 2014 (together, the “Indenture”). The Senior Notes are general unsecured senior obligations of the Company. The Senior Notes are unconditionally guaranteed jointly and severally on a senior unsecured basis by the Subsidiary Guarantors and certain future subsidiaries of the Company. The Senior Notes will have substantially identical terms, other than with respect to transfer restrictions and registration rights, as our original 7.50% senior notes due 2020 that are currently outstanding (the “original 7.50% senior notes”), but will be issued as a separate series of securities and will not be fungible with the original 7.50% senior notes unless and until such time as they are exchanged for additional original 7.50% senior notes pursuant to the terms of the Registration Rights Agreement described herein. The Senior Notes rank equal in right of payment with all existing and future senior indebtedness of the Company, and senior in right of payment to any future subordinated indebtedness of the Company. The Senior Notes are effectively junior in right of payment to any secured indebtedness of the Company to the extent of the collateral securing such indebtedness, and to any indebtedness and other liabilities of any non-guarantor subsidiaries. The subsidiary guarantees rank equal in right of payment with all existing and future senior indebtedness of each Subsidiary Guarantor, and senior in right of payment to any future subordinated indebtedness of each Subsidiary Guarantor. The subsidiary guarantees are effectively junior in right of payment to any secured indebtedness of each Subsidiary Guarantor to the extent of the collateral securing such indebtedness.

Interest and Maturity

The Senior Notes will mature on September 15, 2020. Interest on the Senior Notes will accrue from September 15, 2014 and is payable in cash semi-annually in arrears on each March 15 and September 15, commencing March 15, 2015. Interest will be payable to holders of record on the March 1st and September 1st immediately preceding the related interest payment date, and will be computed on the basis of a 360-day year consisting of twelve 30-day months.

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Optional Redemption

At any time prior to September 15, 2015, the Company may on any one or more occasions redeem up to 35% of the aggregate principal amount of Senior Notes issued under the Indenture at a redemption price of 107.500% of the principal amount, plus accrued and unpaid interest, if any, to the redemption date (subject to the right of holders of record on the relevant record date to receive interest due on an interest payment date that is on or prior to the redemption date), in an amount up to the amount of the net cash proceeds of one or more equity offerings by the Company, provided that:

Prior to September 15, 2016, the Company may redeem all or part of the Senior Notes upon not less than 30 or more than 60 days’ notice, at a redemption price equal to the sum of:

On and after September 15, 2016, the Company may redeem all or a part of the Senior Notes, upon not less than 30 or more than 60 days’ notice, at the redemption prices (expressed as percentages of principal amount) set forth below, plus accrued and unpaid interest, if any, to the applicable redemption date, on the Senior Notes redeemed to the applicable redemption date (subject to the right of holders of record on the relevant record date to receive interest due on an interest payment date that is on or prior to the redemption date), if redeemed during the twelve-month period beginning on September 15 of the years indicated below:

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Change of Control

If a Change of Control (as defined in the Indenture) occurs, each holder of Senior Notes may require the Company to repurchase all or a portion of that holder’s Senior Notes for cash at a price equal to 101% of the aggregate principal amount of the Senior Notes repurchased, plus any accrued but unpaid interest on the Senior Notes repurchased, to, but excluding, the date of repurchase (subject to the right of holders of record on the relevant record date to receive interest due on an interest payment date that is on or prior to the repurchase date).

Certain Covenants

The Indenture contains covenants that, among other things, limit the Company’s ability and the ability of the Company’s restricted subsidiaries to:

Events of Default

Upon a continuing event of default, the trustee or the holders of 25% of the principal amount of the Senior Notes may declare the Senior Notes immediately due and payable, except that a default resulting from a bankruptcy, insolvency or reorganization with respect to the Company, any restricted subsidiary of the Company that is a significant subsidiary or any group of its restricted subsidiaries that, taken together, would constitute a significant subsidiary of the Company, will automatically cause all Senior Notes to become due and payable. Each of the following constitutes an event of default under the Indenture:

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The foregoing description of the Indenture and the Senior Notes does not purport to be complete and is qualified in its entirety by reference to the full text of the Indenture, which components are exhibits to this Current Report and incorporated by reference herein.

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Item 9.01 Financial Statements and Exhibits

(d) Exhibits.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: October 30, 2014

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Exhibit Index